Multi-optical-path photoelectric switch

Abstract

A light emitting portion of a multi-optical-path photoelectric switch comprising: a predetermined number of light emitting devices for emitting lights; a first case having a male connector disposed at one end, a female connector diposed at the other end, a surface between both ends made of a light transmissive resin, the surface through which the lights from the light emitting devices pass; a fixing frame holding the first case, and having the substantialy same length as the first case; and a second case accommodating a portion of the fixing frame while a residual portion of the fixing frrame is projected therefrom, wherein the light emitting units are mechanically and electrically connected to one another by inserting the portion of the fixing frame thus projected of either of adjacent light emitting units into the second case of the other adjacent light emitting unit. A light receiving portion of the multi-optical-path photoelectric switch comprises the similar structure.

What is claimed is: 
     
       1. A multi-optical-path photoelectric switch comprising: a light emtting portion having plural light emitting units, each including, a predetermined number of light emitting devices for emitting lights,   a first case having a male connector disposed at one end, a female connector diposed at the other end, a surface between both ends made of a light transmissive resin, the surface through which the lights from the light emitting devices pass,   a fixing frame holding the first case, and having the substantialy same length as the first case, and   a second case accommodating a portion of the fixing frame while a residual portion of the fixing frrame is projected therefrom, wherein the light emitting units are mechanically and electrically connected to one another by inserting the portion of the fixing frame thus projected of either of adjacent light emitting units into the second case of the other adjacent light emitting unit; and     a light receiving portion having plural light receiving units, each including, the same number of light receiving devices as the light emitting devices,   a first case having a male connector disposed at one end, a female connector diposed at the other end, a surface between both ends made of a light transmissive resin, the surface through which the lights pass to the light receiving devices,   a fixing frame holding the first case, and having the substantialy same length as the first case, and   a second case accommodating a portion of the fixing frame while a residual portion of the fixing frrame is projected therefrom, wherein the light receiving units are mechanically and electrically connected to one another by inserting the portion of the fixing frame thus projected of either of adjacent light receiving units into the second case of the other adjacent light receiving unit.     
     
     
       2. The multi-optical-path photoelectric switch according to claim 1, wherein the fixing frame is made of a metal. 
     
     
       3. The multi-optical-path photoelectric switch according to claim 1, wherein the portion of the fixing frame accommodated with the scond case of each light emitting units is a half length of whole fixing frame length, and the portion of the fixing frame accommodated with the scond case of each light receiving units is a half length of whole fixing frame length. 
     
     
       4. A multi-optical-path photoelectric switch comprising: a pair of main units, each comprising, a first case having a connector disposed at an end, a surface made of a light transmissive resin, for accommodating either of a first predetermined number of light emitting devices or the first predetermined number of light receiving devices,   a fixing frame holding the first case, and having the substantialy same length as the first case, and   a second case accommodating a portion of the fixing frame while a residual portion of the fixing frrame near the connector is projected therefrom; and     a pair of end units, each comprising, a end case having a length to accommodate the residual portion of the fixing frame of the respective main unit, and   a connector for connecting the connector of the respective main unit.     
     
     
       5. The multi-optical-path photoelectric switch according to claim 4, further comprising: a pair of extension unit, each comprising, a first case having connectors disposed at both ends, a surface made of a light transmissive resin, for accommodating either of a second predetermined number of light emitting devices or the second predetermined number of light receiving devices,   a fixing frame holding the first case, and having the substantialy same length as the first case, and   a second case accommodating a portion of the fixing frame while a residual portion of the fixing frame near the connector is projected from one end of the second case and the other end of the second case projects from the fixing frame having a substantially same length as the residual portion of the fixing frame, wherein the residual portion of the fixing frame of the main unit is inserted into the second case of the extension unit, the connector of the main unit connects to the one of the connectors of the extension unit, the residual portion of the fixing frame of the extension unit is inserted into the end case of the end unit, and the other of the connectors of the extension unit connects to the connector of the end unit, so that the main unit, the extension unit, and the end unit mechanically and electrically connect in that order.     
     
     
       6. The multi-optical-path photoelectric switch according to claim 5, the extension units have plural pairs to connect in series. 
     
     
       7. The multi-optical-path photoelectric switch according to claim 4, wherein the fixing frames are made of a metal.